Normal Map

A normal map is a texture map commonly used in 3D computer graphics to simulate high-resolution surface details on a low-resolution model. Instead of increasing the polygon count of a model to capture intricate details, a normal map encodes information about surface normals, which dictate how light interacts with the geometry, creating the illusion of depth and complexity.

Consider a character model in a video game with intricate wrinkles on its clothing or fine details on a brick wall – creating these details through geometry would be computationally expensive. Normal maps offer a more efficient solution. Artists create a high-resolution version of the model, capture its surface details, and then generate a normal map. This map is then applied to a lower-resolution version of the model, preserving the illusion of intricate details without the need for excessive geometry.

Normal maps are crucial for optimizing real-time graphics, especially in video games where performance is a key consideration. By leveraging normal maps, developers can achieve visually detailed and realistic-looking models without compromising the overall performance of the game.

The RGB channels of a normal map encode information about the orientation of surface normals in relation to the model’s geometry. During rendering, these encoded normals interact with lighting to produce the illusion of depth and surface intricacies. The success of normal mapping lies in the collaboration between artists, who meticulously craft high-resolution details, and developers, who implement the technique within the constraints of real-time graphics.